Emboldened by successful drives to reduce smoking, obesity and the use of trans fats in New York city, mayor Michael Bloomberg today opened a new front in healthy living for New ­Yorkers by launching a campaign to reduce ­consumption of salt.

The campaign, called the National Salt Reduction Initiative, aims to cut the quantities of sodium in packaged and restaurant foods by a quarter over five years. The city claims that if the 2014 target is met it will help save many thousands of premature deaths.

Americans consume on average about 3,400 milligrams of salt a day – well above the recommendation of the American Heart Association of less than 2,300 milli­grams. Most of that is out of the individual consumer's hands as almost 80% of salt intake is already added to packaged and restaurant foods and only about 11% added in the home.

High salt levels can raise blood pressure, which increases the risk of heart disease and strokes.

Dr Thomas Farley, New York's health commissioner, said that 1.5 million New Yorkers already suffered from high blood pressure.

"If we can reduce the sodium levels in packaged and restaurant foods we will give consumers more choice about the amount of salt they eat, and reduce their risk of heart disease and stroke in the process," he said.

If the New York initiative takes off it will have potential nationwide implications because most food producers do not have the capability of making low-sodium foods just for the city. Manufacturers who embrace the spirit of Bloomberg's drive are likely to apply the new standards across the country.

Bloomberg's previous efforts to turn New York into a leaner, healthier, smoke-free zone were all met with initial grumbling but longer-term acceptance and appreciation.

A study published last week by Stanford university looked at the impact of the requirement imposed on the city on fast-food and drink outlets to post calorie figures on their menus.

It studied 100 million Starbucks customer receipts and found that the calories in an average purchase at the coffee chain had dropped by 6% since the new posting rule came in and by 26% for those who typically bought food and drink with more than 250 calories in them.

The difference between the salt drive and the previous health initiatives is that this new mission will be purely voluntary. Smoking and trans fats were both banned, and the posting of calories imposed on larger chains, but in this case food manufacturers and restaurants will be encouraged to participate out of concern for public well-being rather than by compulsion.

The mayor's office draws encouragement that such a voluntary approach can work from the experience of the UK, where a similar move to reduce salt levels in foods was launched in 2003 and has already seen a drop in sodium levels of 40% in some products.

Reaction of food producers and sellers has so far been mixed. The New York restaurant association has given its blessing, as have some large food manufacturers such as PepsiCo which makes crisps and the Subway fast food chain. Other big firms including the Campbell Soup Company are remaining aloof from the initiative, saying they will reduce sodium at their own pace according to the capacity of the marketplace.